下丘脑腹内侧核激活对大鼠急性心肌梗死后心脏电活动的影响  

Effect of Ventromedial Hypothalamic Nucleus Activation on Cardiac Electrical Activity After Acute Myocardial Infarction in Rats

作　　者：许骁 李泽衍 周雨扬 聂鹂庆 江洪[1] XU Xiao;LI Zeyan;ZHOU Yuyang;NIE Liqing;JIANG Hong(Department of Cardiology,Renmin Hospital of Wuhan University,Cardiac Autonomic Nerve Research Center of Wuhan University,Cardiovascular Research Institute of Wuhan University,Hubei Key Laboratory of Cardiology,Wuhan 430060,Hubei,China)

机构地区：[1]武汉大学人民医院心内科,武汉大学心脏自主神经研究中心,武汉大学心血管病研究所,心血管病湖北省重点实验室,湖北武汉430060

出　　处：《心血管病学进展》2022年第4期375-379,共5页Advances in Cardiovascular Diseases

基　　金：国家自然科学基金(81970287)。

摘　　要：目的探究激活下丘脑腹内侧核(VMH)对大鼠急性心肌梗死(AMI)后心脏电活动的影响。方法将15只大鼠随机分为对照组、心肌梗死(MI)组和激活组,每组5只。激活组在VMH区域注射化学遗传激活病毒rAAV-hSyn-hM3d(Gq)-EGFP-WPRE-pA2/2,MI组在VMH区域注射空载病毒rAAV-hSyn-EGFP-WPRE-pA2/2。病毒注射3周后,各组接受氯氮平-N-氧化物腹腔注射2周。病毒注射5周后建立AMI模型。对照组大鼠接受假手术处理。造模24 h后,测量各组大鼠心电图以及左心室有效不应期(ERP)。取大鼠脑组织冰冻切片做免疫荧光染色,观察大鼠VMH区域荧光蛋白表达情况,测量各组大鼠VMH c-fos表达量。结果(1)MI组和激活组VMH c-fos表达量均显著高于对照组,且激活组VMH c-fos表达量显著高于MI组(激活组vs MI组:25.39±5.16 vs 18.76±3.52,P<0.05)。(2)与对照组相比,MI组与激活组心率变异性频域分析指标低频功率(LF)升高,高频功率(HF)降低,LF/HF比值升高;与MI组相比,激活组LF升高,HF降低,LF/HF比值升高。上述结果均有显著统计学差异(P<0.01)。(3)与对照组相比,MI组PR间期、QRS波群时限升高,但结果无显著性差异;MI组QT间期显著延长(P<0.01)。与MI组相比,激活组PR间期、QRS波群时限和QT间期均显著延长(P<0.05)。(4)在体电生理实验结果显示,MI组和激活组左心室心尖部、心中部和心底部ERP均显著降低,且激活组ERP显著低于MI组(P<0.05)。结论激活VMH可加重大鼠AMI后心脏电活动紊乱。Objective To explore the effect of ventromedial hypothalamus nucleus(VMH)activation on cardiac electrical activity after acute myocardial infarction(AMI)in rats.Methods A total of 15 rats were randomly divided into control,myocardial infarction(MI)and activated groups,with 5 in each group.The activated group was injected with chemical genetic virus rAAV-hSyn-hM3d(Gq)-EGFP-WPRE-pA2/2 in VMH region,and the MI group injected with empty virus rAAV-hSyn-EGFP-WPRE-pA2/2.3 weeks after virus injection,all rats received intraperitoneal injection of clozapine-N-oxide for 2 weeks.AMI model was established and the rats in the control group received sham operation.24 hours later,ECG and left ventricular effective refractory period(ERP)were recorded.Brains were frozen-sectioned for immunofluorescence staining.Expressions of fluorescent proteins and c-fos were measured.Results(1)The expressions of c-fos were significantly higher in MI and activated groups than control group,and higher in activated group than MI group(activated group vs MI group:25.39±5.16 vs 18.76±3.52,P<0.05).(2)Compared with control group,low frequency power(LF)of heart rate variability index was increased in MI and activated groups,and high frequency power(HF)decreased,the ratio of LF/HF increased.Compared with MI group,LF was increased in activated group,and HF decreased,the ratio of LF/HF increased.There were significant differences on above results(P<0.01).(3)Compared with control group,PR interval and QRS wave duration were increased in MI group,yet with no significant difference(P>0.05),and QT interval prolonged(P<0.01).Compared with MI group,PR interval,QRS wave duration and QT interval were prolonged in activated group(P<0.05).(4)The results of electrophysiological experiments in vivo showed that ERP of the left ventricular apex(LVA),the left ventricular base(LVB),and the median area between the LVA and the LVB in MI group and activation group were significantly shorter and ERP were obviously shorter in activated groups than MI group(P<0.05).Conclus

关 键 词：下丘脑腹内侧核 化学遗传 心肌梗死 心脏电活动 

分 类 号：R542.22[医药卫生—心血管疾病]